Electric jet-wave commutator and interrupter



March 27, 1928. 1,664,031

J. F. G. P. HARTMANN v ELECTRIC JET WAVE COMMUTATOR' AND INTERRUPIER Filed Feb. 25, 1926 A TTORNEY Patented Mar. 27, 1928.

PATENT OFFICE.

JULIUS FREDERIK GEOBG FOUL HARTMANN, OI COPENHAGEN, DENIM ELECTRIC JET-WAVE OOM'MUTATOR AND IN'J.IEZBJBJIPJZ'EB.

Application filed February 25, 1926, Serial No.

, tion of an electric circuit, and particularly to the so-called jet-wave commutators and interrupters which are described for instance in my U. S. patent specifications Nos. 1,306,335 and 1,365,491, and the main object of the invention is to provide an im-- proved auxiliary electrode of solid material or part of the same for use in such devices in order to increase the security of service and in some instances to reduce the electric resistances. The term auxiliary electrode is used herein for designating an electrode different from the main electrode and serving to conduct current into or away from the jet-wave.

In accordance with the invention one or more of the auxiliary electrodes or auxiliary electrode parts coacting with the conductive jet-wave is or are formed as one or more conductive walls of substantial length arranged lengthwise of the direction of propagation of the jet-wave liquid particles at said wall or walls, or nearly in that direction, and extending, over at least one halfwave of the jet, said wall or walls being substantially perpendicular to the plane of the jet-wave which latter, while out by the wall or walls, remains in contact therewith.

The said conductive wall may be formed as a slender wedge arranged in the plane of symmetry of the commutator or interrupter, i. e. in a plane perpendicular to the plane of the jet-wave and passing through the position of the jet when currentless, with its edge against the direction of propagation of the liquid particles so as to cut the jetwa-ve during'its passage of the said wedge.

The invention further comprises other features which will appear from the following detailed description.

0 Referring now to the accompanying drawrugs:

Figure 1 is a diagrammatic view of a jetwave commutator,

Figures 2, 3, 4. and 5 are similar views of jet-wave commutators including certain embodiments of the invention.

Figure 1 shows a commutator of known type which contains a wave-shaped liquid jet, or shortly a jet-wave J, preferably of mercury, which issues from a nozzle N and moves on in the direction of the axis of the 90,469, and in Great Britain larch 25, 1925.

wave figure and, strikes an electrode (main electrode), enerally but not always, a twopart-electro e E E between the component parts E and E Of jWhlCh one or more knives P of insulating or conductive material ordinarily are placed which cut the bends of the jet-wave at the pro er moment during the commutation. The 1et-wave being during its movement towards the double electrode E E, in constant touch with an auxiliary electrode E, will, alternately connect this latter electrode with the electrode parts E and E The jet-wave together with the double-electrode E E and the auxiliary-electrode E thus form a commutator which may be used for the rectification of an alternating-voltage. For this purpose the waves are generally produced by the coaction between a constant magnetic field F and an auxiliary alternating current which is synchronous with the voltage to be rectified. This current may be delivered from the secondary T of a transformer and sent into and out from the jet through the nozzle N and an auxiliary electrode E. Furthermore in drder to make the commutator serviceable for the rectification of the alternating voltage the double-electrode is, and must be, adjusted at such a distance from the field, that the jet-bend is out nearly at the moment in which the alternating voltage alters its sign. i

The improvements more particularly described in the following mainly relate to the various auxiliary electrodes oi such a jetwave-commutator but may also be used in several other apparatus in which a 'jet wave conductor is used for the closing or interruption .of an electric circuit. The general prin- -ci le can best be explained in connection the jet-wave during its movement is cut by the wall, the jet-wave nevertheless being in constant touch with this wall. If the wall i connect tie wall with either the electr e "two knives w, and 10, may be cut the ]et-wave between the parts motion of the part E, or the electrode part E,. In the osition 1 of the jet wave shown, in full ines the electrodes E and E, are connected through the part ab of the jet-wave, and in the somewhat later position 2 shown in dotted lines the electrodes E and E, are

connected through the part cd of the wave stream. Obviously thecondition for an uninterrupted connection between the mainelectrodeE E, and the auxiliary electrode E is that the height of the latter is reater than half the wave-length )t/Q of t e jetwave.

If the electrode E isf-arranged in the plane of symmetry of the commutator as shown in Fi re 2, knives w, and 'w, of conductive or insulating material must generally be placed on either side of the wall to interrupt, at the proper moment, the connection formed b the jet-waves between the electrode parts l i-and E during the first phase of the commutation.

Instead of one single wall E two or more walls arranged on o posite sides of the plane of symmetry of the commutator may be used. An electrode of this type with two walls E, and E, is shown in Figure 3. Here again each wall extends at least over one half-wave of the jet. The mid-most part of the commutator now being left free a single knife to can be positioned here to cut t e jet-wave. The lower edges of the walls E, and E, must be placed at such a level that the jet-wave releases its hold on the edge nearest to that electrode side which the jet-wave is just leaving before the jetwave is cut by the knife. Otherwise the commutation-spark will a pear at said edge, thus in Figure 3 at the eft, instead of at the knife. In order to secure the interrpiption of the connection between the electro side and the -wall, at' the proper moment, appjlied to and E, and the arts E, and E respectively. -The herein-described auxiliary electrodes are mainly adjusted in the direction of the particles of which the jetwave is built up, that is in or nearl in planes perpendicular to the plane of t e jet-wave and radiating from the middle-point of the field F. 1

Experiments have shown; that the wall should preferably be shaped as a slender wedge as illustrated in Figure 4, which rep resents an electrode of the-same kind as that shown in Figure 2. The wedge-shape is preferable because otherwise the jet-wave would run the risk of losing its contact with the electrode. As the liquid particles move along straight lines issuing from the middlewedge-side so that a certain contact pres-.

sure is maintained. Electrodes of this typ: are called wedge-electrodes. They can constructed in many different forms.

Figure 5 shows a wedge-electrode mainly adapted to act in the same manner as the electrodes E, E, illustrated in Figure 3 and consistin of two wedges E, and E However in igure 5 the sldes ofthe main electrode have each been divided into two parts E, e, and E, e, respectively. The two pieces e, and e, are called secondary electrodes. Between the secondary electrodes e, and e, and the neighbouring electrode-pieces .E, and E respectively, resistances 1' have been inserted for the purpose of reducing the short-circuiting-current which arises during each commutation. The various E, E, e,- e, E, including the main electrode E, e s, E and the auxiliary-electrode E, E, are all formed as wed es, and it will be noted that between two we es belon 'ng to the main-electrode there is pl plarts of the electrode aggregate aced at th' sides of the commutator a wedge w, and w,

respectively belonging to the auxiliary electrode. More com ound forms can be pro: duced by augmenting the number of wedges. The advantage of such forms is that they have a comparatively small resistance. On

the other hand it has been found that the compound forms have certain disadvantages which are absent in the simpler electro es and especially in that shown in Figure 4.

Thus as a rule they. demand a jet-wave of rather constant amplitude.

It has been indicated above that the im provements do not only apply to the auxil- 1ary electrode E, the commntated from the commutator. The auxiliary electrode E in Figure 1 which serves for the in- Figure 1, through which troduction of the auxiliary current into the jet-wave may also be constructed in accordance with the present invention. L

It must be particularly noted that in the embodiments shown in Figures 3 and 5 where the walls are laced in a substantial distance from the middle-line of the commutator the length of thewalls need not excurrent is conducted out ceed half a wave-length (X/2) as the waves become shorter towards the sides'of the oom-' mutator. The magnitude half a wavelength is measured along the middle-line of the commutator and has a fixed value, while the waves themselves become shorter'towards the sides of the apparatus as will appear from the drawings. It is thus sufiicient that the wall extends over at least one half-wave of the jet, namely, at the particular point where the wall is placed. The term one half-wave of the jet as used above and in' the following claims is therefore intended to desi ate a variable magnitude depending upon t e particular position of the wall.

Having thus fully described my invention I claim as new and desire to secure by Letters Patent-z 1. In an electric jet-wave apparatusv the combination of means for producing a conductive liquid jet-wave, and an auxiliary electrode member comprising a solid conductive wall of substantial length arranged lengthwise of the direction 0 propa atlon of the jet-wave liquid particles at sai wall and extending over at least one half-wave of the jet, said wall being substantially perpendicular to the plane of the jet-wave, which latter while out by the wall remains in contact therewith.

2. In an electric jet-wave apparatus, the combination of means for producin a conductive liquid jet-wave, an electro e member comprising a solid conductive wall member of substantial length arranged parallel to the direction of propagation of the liquid particles of the 18t-W8V8, and having a length not less than that of one-half wave of the 'et, said conductive wall consisting of a slen er wedge arranged-with its edge against the direction of propagation of the liquid particles so as to cut the jet-wave during its passage of the said wedge, and means comprising a plurality of'maln electrode members cooperating with said jetwave after contact with said first mentioned electrode. 3. Inlan electric jet-wave a paratus, the

' combination of means for pro ucin a conductive liquid jet-wave, an .electro e member comprising a solid conductive wall member of substantial length arranged parallel to the direction of propagation of the liquid particles of the jet-wave, and having a length not less than that of one-half wave of the jet, said conductive wall having a sharp edge and being arranged in the plane passing through the position of the jet when ourrentless with its edge against the direction of propagation of the liquid particles.

4. In an electric jet-wave commutator the combination of means for roducing a conductive llqllld et-wave, a s ender sold conductive wedge arranged in the plane of symmetry of the commutator with its edge against the direction of propagation ofthe liquid particles and forming an auxillary .electrode adapted to constantly remain in contact with the jet-wave while cutting the same,-' a two-part main electrode, the component parts of which are arranged at o posite sides of the plane of symmetry 0 the commutator and adapted to be alternately connected with said wedge-shaped auxiliar electrode through said jet-wave, and a kni e placed on each side of said auxiliary electrode and adapted to interrupt the connection formed by the jet-wave between the component parts of the said main electrode during the first phase of the commutation.

5. In an electric jet-wave a paratus, the combination of means for pro ucing a conductive liquid jet-wave, a plurality of main electrode members cooperating therewith for the collection of current therefrom, and an auxiliary electrode for the delivery ofcurrent thereto comprising a member arran ed in the direction of propagation of said etcurrent thereto, comprising amember having surfaces cooperating with the jet-wave in the plane of vibration of said jet-wave, said surfaces being respectively inclined to each other and to the line of propagation of the liquid particles of said wave.

In testimony whereof I have aflixed my signature.

JULIUS FREDERIK GEORG POUL HARTMANN. 

